ZFS is good, but can lose data, too.Either due to losing power or due to the raid disk system locking up and needing a reboot.Best option for ZFS is still to go directly to a JBOD without any RAID controller in between.

the XFS VOl, was behind a UPS, and on a SAN array. it was a freak power spike... not sure how the XFS was setup it was an old server that i didnt build. we did have a backup, so we just restored it; but because we where also restoring a lot of other things restoring 10TB takes awhile.

me and another Nix guy have been talking for sometime about how we do our filesystems, that we should rethink a few things.which is sorta where this thread idea came from...

BTRFS, seems to be where folks would like to go but its very immature. so everyone is going with ZFS. tho, over the weekend I was reading thru the updated suse11 docs and they now support btrfs with snapper for filesystem snapshots. but the limitations part means "system" restores can not be done because /boot must be ext4, and the kernel can not be snappshoted.so you can only restore files, when it comes to the system, tho a data vol may be cool but databases would be an issue.

upon reading about ZFS; two things jumped out at me one; that ZFS was designed to protect the data on disk. so once its written its a lot safer then with some other filesystems. and two, that ZFS can become "fragmented" tho reading about ZFSfragmentation its not like fragmentation on windows. and apparently there are ways to configure to limit it...

I'd say it depends. Last time I checked zfs allow wasn't implemented yet, but that's probably not a concern in most cases.

Concerning the filesystem itself, though, I agree from what I can judge. I would choose and recommend it over XFS in all cases - except those edge cases that you could make up or rarely see IRL where XFS is better.

Yup, you're correct on that one - built-in privilege delegation is not yet supported; you have to use sudoers correctly if you want to delegate the ability to do zfs admin stuff to non-root users. I don't miss that too much though.

I was under the impression that ZFS makes the assumption that your underlying hardware isn't the filthy pack of lies that consumer grade gear is, and will get into bad shape with few recovery tools if your hardware lies about when data has actually hit the disc?

Uhm no the filthy pack of lies are RAID Controllers who lie about the actual disk layout. Saying "Sure thing, i've written this to disk mr filesystem!" When in reality it hangs in its cache somewhere, waiting to be lost when not battery backed in the event of a power failure.

Consumer grade stuff is usually too stupid to lie, so the assumptions ZFS does work out.

I have definitely heard stories about consumer grade hard drives out there that report writes complete when they are in the drive's cache. Drive caches tend to be much smaller than hardware RAID controllers, so even if they are dirty liars the exposure window is much less. I don't know if this is still a problem with current generation drives, but hardware lying to improve benchmarks is not isolated to any one segment of the computer industry

By the way, it is 2013 and we have 8 core CPUs. Why do hardware RAID controllers without battery backed RAM still exist? Delegating the RAID5/6 checksum calculation to a coprocessor is about the most inefficient and pointless exercise imaginable.

The problem with ZFS is not limited to hardware RAID controllers without battery backed RAM.ZFS gets the same problem with hardware RAID controllers with battery backed RAM, if the RAID controller firmware hangs.

What you want with ZFS are several large JBODs, hanging of a SAS or FCAL card.The problem usually is, that there a lots of offers of external disk systems "with a RAID controller", you can connect to your server. The JBODs are usually only sold as extension boxes to these external disk system.

What I am missing are documented external JBODs, to be connected to SAS or FCAL cards.We had these with SCSI, and I had SCSI PCI-66 cards with 4 external connectors.